1. Field of the Invention
The present invention relates to a transmission power control method and apparatus for setting a maximum output power state of a mobile communication terminal by means of a simulative base station unit (testing instrument) for testing the mobile communication terminal such as a cellular phone.
2. Description of the Related Art
As is well known, a W-CDMA (Wideband Code Division Multiple Access) is proposed as one of the radio communication approach in a third-generation mobile communication system.
Further, while this W-CDMA is employed as a base, there has been made the standardization of HSDPA (High Speed Downlink Packet Access) of a 3.5-th generation mobile communication system (3.5G) in which a packet communication speed is increased.
Moreover, in response to this HSDPA, there has been discussed the standardization of a communication scheme of the HSUPA (High Speed Uplink Packet Access) that enables an uplink function and high speed data communication.
In this HSUPA communication approach, as shown in FIG. 25, communication is made between a base station 1 and a mobile communication terminal 2 of each user, and in signals to be transmitted and received, data and control information to be transmitted and received are multiplexed and incorporated.
In other words, in FIG. 25, a signal to be transmitted from the mobile communication terminal 2 to the base station 1 is an uplink signal (Uplink) 3, and a signal to be transmitted from the base station 1 to the mobile communication terminal 2 is a downlink signal (Downlink) 4.
FIG. 26 is a schematic block diagram depicting procedures for generating the uplink signal 3 in the W-CDMA communication approach.
In other words, as shown in FIG. 26, a data channel DPDCH (Dedicated Physical Data Channel) including data to be transmitted and a control channel DPCCH (Dedicated Physical Control Channel) including control information each are input to an adder section 6 after spectrum-spread by means of spread codes specified at spreading sections 5a and 5b. 
Further, the output added at the adder section 6 is produced as a radio wave to be on the air from an antenna 8 after converted to a high frequency wave at a high frequency section (RF section) 7.
FIG. 27 is a schematic block diagram depicting procedures for generating uplink signals in the communication approaches HSDPA and HSUPA.
In other words, as shown in FIG. 27, in addition to the W-CDMA data channel DPDCH and the control channel DPCCH mentioned previously, the uplink signals in the communication approaches HSDPA and HSUPA incorporate a total of five physical channels, i.e., a control channel HS-DPCCH (High speed Dedicated Physical Control Channel) exerted by an extended HSDPA; an HSUPA data channel E-DPDCH (Enhanced Dedicated Physical Data Channel); a control channel E-DPCCH (Enhanced Dedicated Physical Control Channel). These channels each are input to the adder section 6 after spectrum-spread by means of the spread codes specified at the spreading sections 5a, 5b, 5c, 5d, and 5e. 
The data channel and the control channel configure physical channels.
Then, these five physical channels, as shown in FIG. 28, are individually provided for each of the uplink signal (uplink) 3 and the downlink signal (downlink) 4, and physical channels 9 of the uplink signal (uplink) 3 and physical channels 10 of the downlink signal (downlink) 4 are set at their different frequency bandwidths.
Here, the uplink signal (uplink) 3 includes five physical channels 9, each of which is code-multiplexed, and thus, the physical channels 9 each are stacked in a power direction, as illustrated.
In this case, the important thing is that the total transmission power of the five physical channels 9 of the uplink signal (uplink) 3 to be output from the mobile communication terminal 2 to the base station 1 is defined in the 3GPP (3rd Generation Partnership Project) standard so as not to exceed the predetermined maximum output power PMAX.
In other words, in “6.2.1 UE maximum output power” described in 3GPP TS25. 101 of non-patent document 1 serving as the 3GPP standard, in the case of the W-CDMA communication approach, the maximum output power of the mobile communication terminal 2 is standardized at +33 dBm to +21 dBm into power classes 1 to 4 in accordance with a mobile communication terminal class (UE Power class).
As described previously, in the case where a technique of a new communication approach is standardized, it is necessary to test whether or not a mobile communication terminal developed in order to achieve the communication approach conforms to the performance specified by the standard for the communication approach.
One of the tests of the mobile communication terminals is a test relating to the Maximum Output Power to be measured as the maximum output state of the transmission power described previously, and is specified in “5.2 Maximum Output Power” described in 3GPP TS34. 121-1 of non-patent document 2 serving as the 3GPP standard.
In patent document 1, there is disclosed a technique of controlling transmission power of channels and transmission power of the entire mobile communication terminal, based on a data transmission speed (data rate) of data channels in the mobile communication terminal.
Non-patent document 1: 3GPP TS25. 101 V6.13.0 (2006-10)
Non-patent document 2: 3GPP TS34. 121-1 V7.2.0 (2006-10)
Patent document 1: Jpn. Pat. Appln. KOKAI Publication No. 2003-510950